Magnetic soroban (abacus)



5 A 8 v 1 3| z 16|? A, 8 @w E INVENTOR April 28, 1970 KOGANE HARADA MAGNETIC SQROBAN (ABACUS) 2 Sheets-Sheet 1 Filed Nov. 28. 1967 K oeANE HARADA,

BYUIPMMM 4f VM April 28,1970 KOGANE HARADA 3,508,348

MAGNETIC SOROBAN (ABACUS) Filed Nov. 28. 196'? 2 Sheets-Sheet 2 K OGANE HA RAM INVENTOR United States Patent O 3,508,348 MAGNETIC SOROBAN (ABACUS) Kogane Harada, 9 Ageba-cho, Shinjuku-ku, Tokyo, Japan Filed Nov. 28, 1967, Ser. No. 686,016

Int. Cl. G06c 1/00 U.S. Cl. 35-33 8 Claims ABSTRACT F THE DISCLOSURE Magnetic soroban comprising a rectangular tray, a proper number of rectangular magnetic sheets placed therein the shorter sides of which are approximately twice as wide as beads are and the longer sides of which are kept in touch with each other and at which polarities are established, a film having magnetic permeability placed therein, a beam placed sideways and a proper number of head-travelling rods lengthways over said lilm and beads sensitive to magnetism set in said bead-travelling rods.

This invention relates to a magnetic soroban. The term soroban as used herein denotes abacus and the like. The invention is characterized in that the beads of the soroban are not disorderly positioned even when a considerable shock is given to the soroban or the soroban is placed in a gradient manner. It is particularly suitable as a soroban for use by blind people as well as for ordinary calculation and computation.

The present invention comprises a rectangular tray made of such material as, for example, metal, synthetic resin, wood, etc., rectangular magnetic sheets placed therein the shorter sides of which are approximately twice as wide as the beads and the longer sides of which are kept in touch with each other lengthways and at which polarities are established, a lm having magnetic permeability placed over said sheets, a beam placed along one of the longer sides of the tray, a proper number of bead-travelling rods arranged over the tray and beads sensitive to magnetism set on the said bead-travelling rods.

There have been heretofore offered, for instance as Japanese utility model Patent No. 492,082 (Publication No. 33/ 16,608), sorobans having magnetic films used therein. These prior art sorobans have used a single piece of magnetic sheet therein. Therefore, magnetic attraction is strong at both ends thereof (magnetic poles), and weak in the middle part thereof. Thus, it was impossible to obtain a uniform magnetic force throughout the sheet. A different degree of force is undesirably required in order to move the beads up and down.

Further, when the beads are set on the bead-travelling rods, the beads tend to fall downwardly or tend to stick to each other due to the nonuniform magnetic forces in the rectangular sheet. Due to such disadvantages, it has been impossible to put the magnetic soroban to practical use.

The present invention has overcome the aforementioned problems and disadvantages. This invention is characterized by preventing the beads from falling down and from sticking to each other by creating a uniform magnetic attraction throughout the magnetic sheet. Further, the present invention is characterized by causing beads to stay at a desired position steadfastly and preventing the beads from being disorderly positioned.

The drawings show the preferred embodiment of the present invention. FIGURE 1 is a plan view thereof. FIGURE 2 is a view in section taken as indicated along line A-A in FIGURE 1. FIGURE 3 is a plan view of the magnetic sheet which has been previously used. FIG- URE 4 is a plan view of the magnetic sheet of the present invention. FIGURE 5 is a view in side elevation of the lee bead-travelling rod passing through the bead. FIGURE 6 is a view in perspective of the bead of the soroban for use of the blind person.

Turning now to the specific embodiment of the invention selected for illustration in the drawings, the number 1 designates a rectangular tray which is made of such material as, for example, metal, synthetic resin, wood, etc. The numbers 2 show a plurality of magnetic sheets which are rectangular in shape. The shorter sides 3 thereof are made approximately twice as wide as a bead. The said shorter sides may be slightly more than or less than twice the width of a bead. The longer sides 4 thereof are placed in contact with each other lengthways. The plurality of sheets are of such a size as to be properly arranged within the tray.

The number 5 designates a bead which is made in such manner as to be attracted to the magnetic sheet.

The bead is provided with the smooth bottom surface 6 and may be made of the synthetic resin incorporated with iron powder or nickel powder therein. Or the bead may be moulded from synthetic resin and the smooth bottom surface plated with iron or nickel sheets. Or the bead may be moulded solely from iron nickel sheet. The number 7 designates the bead-travelling rods on which the beads are set. There is provided the beam 8 on the upper parts of bead-travelling rods. The bead-travelling rods are manufactured, inseparably from the beam, so as to constitute a single body. The number 9 designates the metal or synthetic resin sheet having magnetic permeability which will facilitate the travel of the beads.

The embodiment selected for the illustration of the present invention is manufactured in such a manner as to place rectangular magnetic sheets 2, keeping their longer sides 4 in touch with each other lengthway, on the bottom 10 of the rectangular tray, place a film having permeability iixedlythereover in a proper manner, and further place the bead-travelling rods 7 on which beads 5 are set and the beam 8 thereover in a proper manner and x said bead-travelling rods 7 and beam 8 thereon in a manner that the beads S may be kept in slight touch with the film 9 having magnetic permeability,

The illustrated embodiment of the present invention shows the case where a proper number of small rectangular magnetic sheets are arranged in a manner that their longer sides are in contact with each other. However, a single piece of magnetic sheet may be also used, provided that such sheet has the same magnetic property as required for the present invention.

Then, an explanation shall be made as to the function and effect.

As shown in FIGURE 3, a single piece of magnetic sheet has been used in prior art devices. Such device has the disadvantage that magnetic attraction is strong at both ends and weak in the middle part thereof. The beads in the middle have occasionally slipped out of the proper positions. This has made it imposible to make an accurate calculation or computation.

The soroban constructed in accordance with the present invention comprises, as shown in FIGURE 4, a plurality of rectangular magnetic sheets 2 the shorter sides 3 of which are approximately twice as wide as the beads and the longer sides of which are placed so as to be kept in touch with each other lengthways and at which polarities are established.

Accordingly, the soroban of the present invention is different from prior art devices in that each longer end of each sheet is a pole, and the magnetic forces are therefore made uniform. Therefore, beads will not fall downwardly. Bead-travelling rods prevent the beads from being attracted to each other. The up and down travel of beads is not subject to magnetism. The magnetic attraction is Patented Apr. 28, 1970 l made uniform. Thus, it is possible to move the beads up and down regularly, or cause beads to stay at a proper place steadily.

*FIGURE 6 shows the beads of the soroban which is for use by blind persons.

The upper part of the bead is made roundish. It is possible to provide a soroban the beads of which are not made to be disorderly positioned for the use of the blind persons by changing the shape of the bead. i

It will be understood that the descriptive designations sideways, lengthways, upwardly and downwardly and similar terms used herein, refer to the drawings, and not to the orientation of the soroban, since the soroban of this invention may be moved in any position.

What I claim is:

i1. A magnetic soroban comprising a rectangular tray; a plurality of rectangular magnetic sheets on said tray; a magnetically permeable lm on said sheets; a beam positioned on said tray parallel to the longer sides thereof; a plurality of bead-travelling rods positioned over said tray perpendicular to said beam; and a desired number of beads sensitive to magnetism positioned on each of said rods for movement therealong; whereby the shorter sides of said sheets are approximately twice as wide as said beads and the longer sides of saidsheets are positioned in contact with each other and have polarities established thereat.

2. The magnetic soroban according to claim 1 wherein the width of said shorter sides of said sheets are slightly less than twice the width of said beads.

3., The magnetic soroban according to claim 1 wherein said beads are made of synthetic resin incorporating iron or nickel powder therein and are provided with a smooth bottom surface.

4. The magnetic soroban according to claim 1 wherein said beads are moulded from synthetic resin and have smooth bottom surrfaces which are plated with iron or nickel sheet.

5. The magnetic soroban according to claim l1 wherein said beads are moulded from iron or nickel sheet.

6. The magnetic soroban according to claim 3 wherein said beads have roundish upper parts for use by blind persons.

7. The magnetic soroban according to claim 4 wherein said beads have roundish upper parts for use by blind persons.

8. The magnetic soroban according to claim 5 wherein said beads have roundish upper parts for use by blind persons.

References Cited UNITED STATES PATENTS 2,654,164 l0/1953 Seidenberg 35-33 2,857,686 10/1958 Blake 35-33 2,872,742 2/1959 Schott -..i 35--33 yEUGENE yR. CAPOZIO, Primary Examiner W. H. GRIEB, Assistant Examiner 

